In recent years, fuel cells have been largely paid attention to as a new energy source. Fuel cells include solid oxide fuel cells (SOFC), molten carbonate fuel cells, phosphoric acid fuel cell and solid polymer fuel cells. Among these fuel cells, solid oxide fuel cells do not necessarily need to use a liquid constituent and are capable of reforming a hydrocarbon fuel in their interior when the hydrocarbon fuel is used. Hence, research and development on solid oxide fuel cells is being actively carried out. For example, Patent Literature 1 describes one example of solid oxide fuel cells.
Patent Literature 2 describes use of an air electrode containing a perovskite-type oxide represented by ABO3.
Patent Literature 1: Japanese Patent Laid-Open No. 2010-3662
Patent Literature 2: Japanese Patent Laid-Open No. 2008-305669